Re: [PATCH] dmaengine: ti: k3-udma: Report short packet errors

["Péter Ujfalusi" <peter.ujfalusi@gmail.com>]

On 03/01/2024 11:07, Jai Luthra wrote:
> Propagate the TR response status to the device using BCDMA
> split-channels. For example CSI-RX driver should be able to check if a
> frame was not transferred completely (short packet) and needs to be
> discarded.

Make sense,

Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>

> 
> Fixes: 25dcb5dd7b7c ("dmaengine: ti: New driver for K3 UDMA")
> Signed-off-by: Jai Luthra <j-luthra@ti.com>
> ---
>  drivers/dma/ti/k3-udma.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
> index 30fd2f386f36..037f1408e798 100644
> --- a/drivers/dma/ti/k3-udma.c
> +++ b/drivers/dma/ti/k3-udma.c
> @@ -3968,6 +3968,7 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
>  {
>  	struct udma_chan *uc = to_udma_chan(&vc->chan);
>  	struct udma_desc *d;
> +	u8 status;
>  
>  	if (!vd)
>  		return;
> @@ -3977,12 +3978,12 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
>  	if (d->metadata_size)
>  		udma_fetch_epib(uc, d);
>  
> -	/* Provide residue information for the client */
>  	if (result) {
>  		void *desc_vaddr = udma_curr_cppi5_desc_vaddr(d, d->desc_idx);
>  
>  		if (cppi5_desc_get_type(desc_vaddr) ==
>  		    CPPI5_INFO0_DESC_TYPE_VAL_HOST) {
> +			/* Provide residue information for the client */
>  			result->residue = d->residue -
>  					  cppi5_hdesc_get_pktlen(desc_vaddr);
>  			if (result->residue)
> @@ -3991,7 +3992,12 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
>  				result->result = DMA_TRANS_NOERROR;
>  		} else {
>  			result->residue = 0;
> -			result->result = DMA_TRANS_NOERROR;
> +			/* Propagate TR Response errors to the client */
> +			status = d->hwdesc[0].tr_resp_base->status;
> +			if (status)
> +				result->result = DMA_TRANS_ABORTED;
> +			else
> +				result->result = DMA_TRANS_NOERROR;
>  		}
>  	}
>  }
> 
> ---
> base-commit: 610a9b8f49fbcf1100716370d3b5f6f884a2835a
> change-id: 20240103-tr_resp_err-9f4eebbdcd3b
> 
> Best regards,

-- 
Péter